There has been an increasing desire to produce smaller and smaller devices in the fields of, among other things, chemistry, biology, electronics and mechanical devices. When the devices approach the size of biological cells, the technology is often referred to as nano-scaled or as nanotechnology. The field of nanotechnology has already proven useful for numerous applications; however, many issues still exist in the development and implementation of nanotechnology.
Some applications of nanotechnology require characteristics of nano-scale structures called nanowires. A nanowire is a wire of dimensions of the order of a nanometer (10−9 meters). Many types of nanowires exist, including metallic, semiconducting, and insulating. They have shown promise in mechanical, chemical, and electrical applications.
There has been growing interest in the formation of new molecular components built with a “bottoms-up” approach: small molecularly-precise parts coming together to become larger ordered complexes, all orchestrated by a series of controlled assembly events. Proteins have proven to be useful building templates for assembling metallic material, with such biologically-inspired examples as nanowires made from amyloidal fibers and peptide nanotubes, and nanoparticle arrays made from heat shock proteins. For additional information regarding device-implementation and manufacturing approaches for nanotube and nanowire structures, reference may be made, for example, to U.S. Pat. No. 5,916,642, U.S. Pat. No. 6,465,132 and U.S. Pat. No. 6,762,331; each of these references is fully incorporated herein by reference.
While nanotechnology has progressed, many challenges remain. For example, applications involving applying metal to the exterior of a protein polymer result in the metal encasing the protein polymer along the length of the polymer, and thus, the protein polymer loses its ability to interact with other molecules. Moreover, it can be difficult to control the thickness of the metal applied to the polymer.
Additionally, producing synthetic organic nanotubes and creating the nanowires inside the nanotubes requires the nanotubes to be synthesized using laboratory controlled organic chemistry, often increasing the production costs and creating problems with producing large quantities of the nanotubes. It is also difficult to control the size of the nanotubes resulting in unwanted variations in the nanowires created.
For these and other reasons, the manufacture and implementation of nanowires has been challenging.